A fact that trappers have known for years, and which present day hunters are just becoming to fully appreciate, is that wild animals as a whole will rely more heavily for their survival upon their sense of smell, than all of their other senses combined.
Wild animals use their noses for three very important reasons: food, sex, and survival. With respect to food, the animal will rely upon its sense of smell to locate and identify edible substances. With respect to sex, animals use their sense of smell to detect scent marked territories of competing males; as well as, to track females in heat and identify the receptive females among groups of females. With respect to survival, animals use their sense of smell to alert them to the presence of man, manmade objects such as traps, and natural dangers such as fire.
Obviously if a hunter or trapper desires to overcome the animal's highly developed sense of smell, they must either nullify the animal's advantage, or use that advantage against the animal. In the first instance, masking lures were developed to negate the odor of man and/or manmade objects in the animal's natural environment. In the second instance, aromatic food scents and sex scents were developed to lure animals to the source of the particular aroma producing compound.
The whitetail deer is this country's premier game animal in terms of money spent and man hours expended during the hunting season. In addition, the whitetail deer possesses character traits that make this species particularly susceptible to the use of lures, masking scents and attractants.
To begin with, whitetail deer unlike other species such as mule deer, elk, moose, etc. are considered to be very territorial and somewhat predictable relative to their daily activity patterns (e.g. whitetail deer will feed and bed down in the same general area for extended periods of time).
In addition, when it comes to mating, whitetail bucks become very predictable in their daily patterns and activity. Whitetail bucks create two different types of "scrapes", one of which is a territorial scrape and the other of which is a mating scrape, and on occasion a territorial scrape will serve both purposes.
Essentially a "scrape" consists of a generally circular area on the ground that has been cleared of all leaves and debris by a buck pawing or scraping the area clean with his hooves.
While territorial scrapes are maintained year round, mating scrapes appear only during the breeding season and can be distinguished from territorial scrapes on the following basis. An active mating scrape will always be clear of debris and exhibit signs of recent pawing. A mating scrape will also bear evidence of recent urination either through odor or discoloration of the soil; and, in most areas a mating scrape will be positioned beneath an overhanging branch whose ends exhibit signs of chewing by the buck who is maintaining the scrape.
As a result of the foregoing situation "scrape hunting" (i.e. hunting in the vicinity of an "active" scrape) has become recognized as an extremely effective strategy for bagging whitetail bucks. In addition, variations of the scrape hunting technique have been developed to increase the hunter's chances of bagging the "dominant" buck in a given territorial area.
When a hunter finds an "active" scrape in the woods, all that he or she can be certain of, is that one of the sexually mature bucks in the area will be visiting that particular scrape on a regular basis, and this buck may or may not be a dominant buck.
In the absence, or in lieu, of finding an active scrape, the hunter now has another technique available to him; in that, he can create a "mock" scrape by imitating a buck's actions in clearing an area in an appropriate location and depositing commercially obtained urine from a doe in heat on the scrape.
In addition, for added realism the hunter may also add urine from a buck to create the sensory illusion that a strange buck has entered a dominant buck's territory, established a breeding scrape, and has had at least one receptive doe visit the scrape and indicated her willingness to be bred.
Given the cost of the commercially available sex lures, it is impractical to simply douse a mock scrape with buck and/or doe urine and hope that the scent will not evaporate or be washed away by rain before a dominant buck will have located the hunter's love trap. It is also impractical to continually "freshen up" the mock scrape by periodic application of the urine compounds; in as much as, each visit will also necessarily entail leaving human odors in the vicinity of the mock scrape which would be counterproductive. productive.
Obviously a need has arisen for a slow release liquid lure dispenser that may be positioned over a mock scrape and left for extended periods of time without replenishment. As of this date the only known commercial lure dispensers involve inverted receptacles having a straight gravity feed of the liquid contents of the receptacle; and, these devices were obviously developed for the sole purpose of promoting the consumption and increased sales of the urine suppliers, and did not take into consideration the limited financial resources of their customers.